


Preheat to max

by kotosk (Kotosk)



Category: Fullmetal Alchemist - All Media Types
Genre: Alpha!Ed, Alpha/Beta/Omega Dynamics, Breeding, Daddy Kink, Double Penetration, Knotting, M/M, Mating Cycles/In Heat, Omega!Roy, Teasing, adult ed and al, alpha!al, bby roy, reverse verse
Language: English
Status: Completed
Published: 2019-06-27
Updated: 2019-06-27
Packaged: 2020-05-26 00:43:38
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,574
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19381660
Author URL: https://archiveofourown.org/users/Kotosk/pseuds/kotosk
Summary: Fortunately for Roy, they had quickly discovered that teasing him speeds up the preheat stage, forcing it into a full-blown heat and allowing it to pass faster. Unfortunately for Roy, they're also mean fuckers who enjoy teasing him way more than appropriate.





	Preheat to max

**Author's Note:**

> bringing you sin in textual format this time, just casually wrote this while waiting for/in buses lmao  
> a huge massive thank you to [LadyMerlin](https://archiveofourown.org/users/LadyMerlin/profile) for betaing this <333

Ed rolls his shoulder as he nears their house, the metal in his body is reacting to the upcoming rain and the ache of it has been slowly building up the entire day at work. He let Al leave earlier for the same reason and the doubled share of paperwork had kept him even longer than he’d planned. Ed dimly wonders if his lovers got around making dinner as he reaches the front step. He opens the door to the faint sounds of Roy moaning and the sweet scent of an omega going into a preheat.

So much for dinner, then. 

Closing the door, Ed tracks the source of the scent, shrugging his uniform jacket off as he goes, the pain in his automail shoulder momentarily forgotten. Walking into the kitchen, he’s greeted by the sight of Roy spread on the table, chest down, gloriously naked and with his ass on display, while Al sits in the chair behind him and thoroughly eats him out. The scent is much thicker there, Roy's and Al's pheromones mixing together, and it smells divine, sets Ed's blood ablaze and makes his teeth itch with the desire to claim his mates. Ed leans against the kitchen doorway, content to enjoy the view for a while. Al sends him an amused glance, his movements steady and sure as he makes Roy writhe on the table, trying to simultaneously get away from the intense sensation and push back to get more of it. Roy's slick is dripping down his thighs, covering Al's chin and fingers and Roy's ass where Al's grabbed it to pull him closer. Ed wants to lick them both clean.

"Starting without me? Rude, Al," he says, feigning offence, glad that at least one of them had been there to tend to Roy's starting heat.  
  
Roy startles at the sound of his voice, choking on a moan as he whips his head up to look at Ed, wide-eyed and beautifully flushed. Al chuckles and brings his attention back to the matter at hand as he slides his fingers in and rubs Roy’s prostate with merciless precision.  
  
"You were late," Al's hand never slows and his reply is almost lost in Roy's wail. Roy arches his back, pushing up on his toes in an attempt to escape the overstimuation, and Al allows him to drop back on table with a soft thud, panting.  
  
Ed forces himself to walk slowly, reaching Al with carefully measured steps and fisting his hair, using his grip to tilt Al’s head until he can lick at his chin and follow the trail of slick to his mouth.The flavor bursts on his tongue, the sweet tangy taste of a ripe, fertile little omega gets him high better than any alcohol, and by the time he’s licked Al’s mouth clean, he's almost panting himself. Al lets him, deceptively pliant and submissive under his lips. They both turn to look when Roy whines at being ignored, and Ed can't resist the urge to sink to his knees and lick at his thigh, following the trickle of slick up and biting at the flesh where Roy's thigh meets his gorgeous ass. Roy lets out a quiet, choked ‘ _ah_ ’, and Ed's cock throbs, a heavy weight setting in where his knot would form. 

“Good boy,” he says, and the rumble in his voice is close to a growl. Roy shudders in response, a fresh wave of pheromones hitting the air so hard it takes a considerable effort not to knot right there and then. They’ve used bottled pheromones to induce knotting, before, and it doesn't come near the real thing, their omega, their _mate_ .

“He really is,” Al agrees. He looks unaffected, the only evidence of his broken composure are his dilated pupils and the intense scent of an aroused alpha about to knot. “Aren't you, Roy?”

Roy mumbles something into the table surface that sounds like a mix between ‘fuck me’ and ‘fuck off’. Ed snorts as he gets up and drops into his chair, finally unzipping his pants and pulling his aching dick out. Al shakes his head and does the same. The sight of his brother’s thick cock, smooth surface interrupted with the bump of a swelling knot, makes Ed's mouth water, and his ass clenches at the thought of having it inside him; perhaps after they've dealt with Roy’s first wave of heat. He pulls the glove off his flesh hand with his teeth, squeezing his bare fingers around the swelling knot and gasping in relief. 

“You aren't making this easier for yourself, you realize," Al chides as he stands closer to Roy, pinning him to the table with his hips, cock nestling snuggly against his ass when Al grinds against him. There's something incredibly indecent about seeing their omega completely naked while they're both fully clothed, and Ed's dick is leaking all over his hand as he strokes himself to the sight in front of him.

Roy tries to rise in his elbows before Al grabs his neck and pushes him back down, his automail shoulder clanking against the table as he succumbs. 

“Daddy, _please_ ,” Roy writhes in his hold as he begs, and Ed has never wanted him more. Al leans down and replaces his hand with his teeth, neatly covering his bite mark on Roy's right shoulder, just above the automail metal. Ed's own mark burns in sympathy as he yearns to renew the bite on Roy's left shoulder.

Roy gasps, both at the teeth in his flesh and the feeling of being stretched as Al pulls his ass higher, angles his hips and slides inside him, still pinning Roy down as he starts to pound him hard, rough thrusts accompanied by wet percussion of skin on skin and Roy's broken moans. His voice gains fervor and crests to a sharp cry when Al wraps his hand around his cock and forces him to come with a few calculated strokes, making him stain the tabletop and his stomach and Al's hand with his come. Roy looks ready to cry, flushed and feverish, and Ed knows it's not enough, not until he comes with a knot ground into his prostate. 

The air is hot and heavy with their mingled scents, and Ed has to stop touching himself for fear that he’ll knot his own hand. He notices the coffee mug which he’d left there that morning, sitting precariously close to the edge of the table, and uses the reprieve to push it to a safer distance, where Al's increasingly rough thrusts won’t threaten to send it over the edge. Roy barely manages to get air in his lungs only to waste it on a desperate “daddy, please, I can't-” before Al growls, pushing in deep and forcing his swollen knot in.

Roy wails as he thrashes on the table, struggling to push back on the knot, before finally stilling and trying to catch his breath. Al slowly releases his neck, presses a kiss in the center of the bite mark, then pushes himself upright, still mostly covering Roy with his body. He winks at Ed and brings his hand up to lick Roy's come off it, baring his neck in invitation as he does so. 

Fortunately for Roy, they had quickly discovered that teasing him speeds up the preheat stage, forcing it into a full-blown heat and allowing it to pass faster. Unfortunately for Roy, they're also mean fuckers who enjoy teasing him way more than appropriate. 

“Don't you _fucking_ dare,” Roy warns, accurately interpreting their silent communication, even though he still looks dazed and intoxicated out from the knot pressed inside him. He sounds resigned though, since he too, knows that they’re all a bunch of assholes (although Roy, due to his young age and lack of practice in fine arts of assholery, could only be considered a little shit and a pain in Ed's ass. Literal pain, as he's grown considerably taller to Ed's great dismay.)

Swearing earns him a sharp slap on the ass from Al, making him gasp and jolt and then whine when the knot shifts inside him. Al sends Ed a look of fake disapproval. 

“See? I told you your swearing was going to rub off on him, brother.”

“Oh, I'm gonna rub off on him alright,” Ed wiggles his eyebrows and reaches out to cop a feel of Al's wonderful ass, snatching his hand back before Al can smack it, too. 

He gets up and noses Al's neck before tugging the collar of his shirt aside and sinking his teeth in. Their bites never took on each other but, apparently, it’s enough to trick the body into thinking there's a danger present, which makes the knot deflate. Ed supports him through the brief moment of dizziness it brings and Roy whines, high pitched and disappointed when Al's cock leaves his body. Al’s come, mixed with Roy's slick, starts to seep out and Ed collects it with his thumb before pushing it back in. Roy's breath hitches. 

“Don't wanna waste any, do we,” Ed says softly, bringing his gloved hand to tease Roy's cock with a slight touch. Roy shakes his head, the tips of his ears getting even redder. 

He grunts and wiggles his ass, sending Ed a glare over his shoulder when he doesn't put his dick in fast enough. Ed can't really deny him anything so he obeys, presses the head of his cock to Roy's hole and sliding inside. Roy's wet and searingly hot and deliciously tight around him, and Ed would be lying if he said he hasn't spent the entire day thinking about doing exactly this. 

“Good boy,” he murmurs into Roy's neck, kissing the tender skin below his ear. After watching Roy getting plowed by Al, Ed barely manages a few thrusts before his knots catches and he finally sinks his teeth into his bite mark on Roy's shoulder, holding him close. Roy clamps down on his knot, and Ed rolls his hips through it, making sure to grind into his sweet spot. Roy's knees give out and he collapses, trembling in Ed's arms.

“Daddy,” Roy sighs, breathless and sweet. He reaches to stroke himself but Ed catches his hand, presses it to the small of his back, automail arm following next. Roy growls, the sound sending a wave of goosebumps down Ed's neck. He exchanges a grin with Al and rolls his hips again, savoring the way Roy clenches around him and his growl breaks into a mewl. The closer he is to the full heat, the more feisty he gets, and sometimes Ed wonders how on earth he was ever supposed to handle Roy alone. Al hugs him from behind, holds him safe and tight, nosing behind his ear, and for one delightful second Ed thinks he's going to get that knot sooner than he expected. 

Al's teeth clamp on Roy's mark on his shoulder, and Ed can't help but gasp. A surge of adrenaline shoots through him, clearing the pheromone induced fog in his head, and the pain from a knot deflating too fast mixes with pleasure in such a heady way it takes a considerable effort to stay upright. Al holds him through it, wetly mouthing at his neck as they wait and watch Roy stubbornly trying to wrench his arms free. He's starting to growl again, the accelerated heat being more intense and sharp than it would otherwise have been. Al takes a step back, leaving his back chilly after their shared warmth as Ed carefully slides out and sets Roy free. 

Roy bolts upright, turning as he goes, and Ed catches Al's ‘oh shit’ expression, torn between the sudden assault and the inability to fight their omega when Roy wrestles him on the floor. Ed really wants to feel proud that their lessons were effective but pride isn't the emotion he experiences when he watches Roy straddling Al and wasting no time before sliding onto his cock and riding him with desperate abandon. He spends a few seconds just taking it in - the way Roy's ass bounces off Al's hips, Al's hands gripping his waist to help him move, Roy's moans breaking into a growl every time Al tries to slow him down. 

Ed kneels behind him, sets his knees on the side of Al's thighs. 

“Room for one more?” he asks more than a little hoarse, because no matter how often they do this, it still amazes him how well Roy takes both his alphas, knots and all. 

Al snorts. Roy slows down to a stop, clearly beyond words at this point, breathing hard through his mouth as he waits for Ed. He's dripping slick and come all over Al, and on some deep instinctual level it makes Ed want to add more, to replace what's been lost and ensure their omega is properly bred. 

He presses himself against Roy, where he's already pulled taut and thin around Al's cock, and slowly, carefully pushes in. Al puts his hands on Roy's hips, to hold him still against the intrusion and Roy groans, low in his throat and desperate as his body gives way. Ed pushes him down into Al's waiting embrace when he's bottomed out, stroking his back as they both praise him, an endless stream of “good boy, you're taking it so well, our beautiful boy, you're so good for us, our little omega, I love you so much-”. Roy bites into his mark on Al's shoulder as if it helps him to anchor himself against the pleasure when they begin to move, one in and the other out, taking care not to move too fast or rough while he adjusts. 

Soon enough Roy begins to roll his hips back, meeting them halfway, and Ed speeds up, lost in the feeling of their cocks sliding together in Roy's tight grip. Al keeps running his hands up and down Roy's back, petting his hair as he croons softly in his ear. Roy is sobbing with each thrust, teeth still latched on Al's flesh, and he's getting tighter with each passing second. Roy's locking on them and the pheromones of a riled up omega provokes them into knotting, together. Roy wails when both their knots set into place, securely tying them together. Ed bites into his shoulder, a bit under his mark (damn this little shit for getting taller) as he comes, enough that when they're done Roy's belly is going to bulge with it, and the alpha part of his brain is immensely pleased at the thought. 

Roy's purring, soft and satisfied and kitten-like, and Ed's own chest resonates with a deep rumble as he sits back, trying not to put too much weight on Al’s automail port. He joins in Al's exploration of Roy's back, sliding his hands down to his ass and lower to his trembling thighs, massaging the tired muscles. Roy tucks his face in Al's neck and stretches a bit, working out any kinks he might've got during their mating, making them both hiss when it pulls at the knots. 

The kitchen is silent save for their combined purring, and Roy is quickly falling asleep after the exercise they put him through. 

“We should get him into the nest before the heat flares up again,” Al murmurs as not to disturb him. 

“Yeah,” Ed agrees just as quietly, but none of them move for a long time. 

**Author's Note:**

> the title is a pun cos roy gets a bun in the oven ;)
> 
> see more of the reverse au [here](https://kotosk.tumblr.com/tagged/reverse-au)


End file.
